Search Documents

By Ke Yang

In Chinese coal mines, extraction of deep, highly gassy soft coal seams sandwiched between soft floor and soft roof in complicated geology is commonly encountered. How to safely and efficiently excavate such seams is a very significant and important problem. It has been a focused research area in recent years. By combining the characteristics of fully mechanized longwall mining methods such as large cutting height and mining along the dip, an integrated method and technologies for the Zhangji Coal Mine were developed. This technology includes the design of a complicated geological exploration system, optimization of mining method and working face parameters, control of rock pressure and high levels of gas, reliability model of the production system, and selection and compatibility of equipment. Engineering practice shows that the integrated technology was successful in mining these complicated seams. This study not only enriches the mining method, but also improves the coal mining practice, especially ensuring both safety and productivity under complicated geological conditions.

Jan 1, 2009

By Hillis R

As part of BHP Iron Ore's policy and goal of achieving a high standard of environmental management within its operations, a protocol for mine closure has evolved. The need to demonstrate sound environmental management with respect to site decommissioning meant that a comprehensive, environmentally sensitive closure protocol was required. Within this framework, a four-phase protocol was developed, the first phase was the determination of objectives in relation to site rehabilitation and end land use. The second phase was the determination of the process required to achieve these objectives. The third phase was the application of this process in a site specific manner. The fourth and final phase was monitoring of the site with regard to the achievement of determined objectives. The protocol was originally developed to direct the closure and decommissioning of the Goldsworthy site in 1992. This being the first total site decommissioning for BHP Iron Ore. Since that time the protocol has been successfully utilised for the closure of the Yampi (Koolan Island) operations (in 1993/94) and the Shay Gap/Nimingarra Operations (in 1994/95).

Jan 1, 1996

By Kevin Sierra, Orfelinda Ávalo, David Martínez, Julio Guizado, Edwilde Yoplac

Los relaves mineros son un subproducto común del proceso de recuperación de los metales y los minerales. En general, consiste en un lodo líquido compuesto de agua y partículas finas de metales y minerales. En la actualidad estos relaves generan serios impactos ambientales provocados principalmente por su toxicidad, al reaccionar con el agua y el oxígeno. Existen diversos estudios que buscan alternativas para tratar estos materiales de manera ecológica para mitigar los impactos ambientales que puedan ocasionar.

Sep 29, 2023

By Natalie Swan, Carlos Santana

La ejecución de programas de monitoreo biológico es un desafío para la gestión ambiental de proyectos mineros, principalmente por la alta demanda de recursos y tiempo que requiere y la poca certeza sobre sus resultados. Por ello, se presenta el uso del ADN ambiental como una alternativa de calidad y probada eficiencia. La aplicación de análisis de ADN ambiental en un programa de monitoreo implica tener en cuenta aspectos sobre la ecología del ADN ambiental, las etapas requeridas para su análisis y el estado de desarrollo de las distintas aplicaciones existentes.

Sep 30, 2022

By Julio Mondragon, Harry Chaca, Dalila. Salinas

En Compañía Minera Atacocha SAA, en busca de mejoras operativas y en la rentabilidad de la operación, se inició el minado por tajo abierto de las estructuras mineralizadas que se encontraban en superficie. A diferencia de otras minas a tajo abierto (explotación de yacimientos porfiríticos y epitermales de alta sulfuración), la operación que se desarrolla actualmente en Atacocha se basa en el minado de estructuras vetiformes de un yacimiento epitermal intermedio. Además, el desarrollo de esta nueva operación no buscó centrarse en la recuperación del mineral que se dejó de minar en los tajos antiguos o del relleno de alta ley que se dispuso en los mismos.

Sep 1, 2017

By Jorge Blacker Bendezú

Existen historias registradas sobre descubrimientos de ciertos elementos de la Química que mostraban propiedades especiales de difícil identificación. En este grupo de elementos químicos (17) se encuentran "las tierras raras" que, conjuntamente con otro grupo de sustancias estratégicas, contribuyen al cabal desarrollo de la ciencia y su correcta aplicación mediante su permanente progreso tecnológico. Por ello, el presente texto señala los mitos y realidades sobre estas "tierras raras" y otros metales estratégicos (comercio, alternativas de explotación y costos)

Jan 1, 2014

By Erin Leyson, Daniel Henrique

Este artículo se centra en el desarrollo de un modelo innovador denominado "Plataforma de Desarrollo Regional" (PDR), el cual es aplicado en la región minera de Cerro de Pasco - Perú, y es impulsado por Nexa y Palladium como parte de la cartera de proyectos nombrada “Legado Positivo Pasco”. Este modelo busca fortalecer el ecosistema de desarrollo local, y disminuir su dependencia económica en la minería. Con este fin, diversas estrategias son implementadas, estas incluyen encadenamientos productivos, acceso a financiamiento, promoción de emprendimiento e innovación, y atracción de inversiones de otras empresas para invertir en la producción local.

Sep 29, 2023

By Juan Manuel Rivera Poma

El presente trabajo describe los métodos empleados para una buena administración y control de la fuerza laboral a través de la aplicación de técnicas en los temas de determinación de la carga de trabajo, los requerimientos del personal, distribución del personal a los requerimiento actuales de la labor y un sistema de control permanente de la fuerza laboral. En este sentido, fue CENTROMIN-PERÚ, quien realizó los análisis técnicos de los recursos humanos y costos por intermedio del Departamento de Ingeniería Industrial-División Sistemas y así mejorar la productividad y la eliminación de gastos innecesarios de la mina.

Nov 20, 1978

By Alfred Weiss

These volumes report on the study initiated by the U. S. Bureau of Mines to develop and apply a methodology to quantitatively assess the probability and potential benefits of technological innovation over the next twenty-five years. The potential was recognized for new technology to solve copper industry problems in the United States. Objectives of the study were to: (1) Develop a methodology to obtain the opinions of mineral experts about future events -their likelihood of occurrence, and, conditional on occurrence, when and to what extent they are likely to occur; (2) Identify, select, and describe potential technological innovations which would have significant impact on copper production; (3) Implement the methodology and obtain the opinions of the mineral experts regarding selected copper technologies; and (4) Analyze the expected future benefits of successful technological innovations :n the copper industry. Although individual technologies are continuously examined throughout the copper 'community', this study is the first known comprehensive forecast of future copper technology. This study is also believed to be unique 1n that it represents the consensus opinion of over sixty expert copper technologists on the expected use of innovative technology in the industry over the next 25 years. The report is contained in three volumes.

Jan 1, 1983

By D. E. Welcome, T. W. McDowell, R. G. Dong, S. F. Wiker

Workers using vibrating hand tools have the potential for developing health problems associated with repeated forceful actions and exposures to hand-transmitted vibration. Hand-arm vibration syndrome (HAVS) and other hand-arm system disorders have been associated with such exposures.1-2 To better assess health risks, comprehensive evaluations of these exposures must include quantitative assessments of hand-tool coupling forces; unfortunately, no standardized method for quantifying hand forces exists. Handle instrumentation may be ill-suited for some field environments. Psychophysical force-recall techniques may provide alternatives to handle instrumentation. A thorough understanding of the effects of vibration and other factors on force-recall accuracy and reliability is important before such methods are applied in risk assessments. Methods In this study, the effects of vibration and other factors on the accuracy of psychophysical force-recall were explored in two experiments. Twelve male subjects participated in the first experiment. The second experiment employed 20 participants (10 female, 10 male). In each experiment, participants applied specific grip and push forces to an instrumented handle mounted on a shaker system. Participants were exposed to sinusoidal vibration at frequencies that ranged from 0 Hz to 250 Hz. Three levels of applied force (low: grip = 15 N/push = 25 N, medium: grip = 30 N/push = 50 N, and high: grip = 45 N/push = 75 N ) and two levels of vibration magnitude (low: ANSI 4-8-hr limit and high: ANSI <0.5-hr limit)3 were examined. During the vibration exposure period, participants were provided with visual feedback while they attempted to “memorize” the applied grip and push forces. At the conclusion of the vibration exposure/force memorization period and a controlled rest period, the participants tried to duplicate the grip and push forces on a non-vibrating handle without the aid of visual feedback. The effects of different vibration frequencies, vibration magnitudes, and grip and push force levels were tested in a random order from trial to trial. Results Participants tended to overestimate grip and push forces. Depending on exposure conditions, error means ranged from 2 N to 10 N. The ANOVA revealed that force-recall errors for exposures between 31.5 Hz and 63 Hz were significantly higher than those at other vibration frequencies (p < 0.05). The frequency effect is depicted in Figure 1. Error means were greater when participants were exposed to the higher vibration magnitude (mean = 9.1 N, 95% CI = 8.2-10.1 N) when compared with the lower vibration magnitude (mean = 4.9 N, 95% CI = 3.9-5.8 N) (p < 0.05). The effect of vibration magnitude is shown in Figure 2. The average error for

Jan 6, 2006

By Dave Kay, Young-Suk Song

To meet the needs of South Korea's rapidly expanding economy, a large number of infrastructure projects are under way to improve transportation efficiency within the nation. These projects include high-speed rail links between major population centres and improvements to the road network. Being densely populated and geographically mountainous, infrastructure development in Korea requires a significant amount of tunnelling. Owing to the predominantly hard granitic nature of rock, drill and blast is the preferred method of tunnel advance. The Korean tunneller, however, faces the same pressures as those of his international counterpart in that both cost and production targets need to be achieved while meeting expectations of both community and regulator.

Jan 1, 2005

By Raúl Prebisch

"El presente texto es un análisis continuo y sistemático de la realidad latinoamericana donde se revisa las transformaciones estructurales para abrir cauce al desarrollo, la acumulación de capital y distribución del ingreso, cooperación internacional y estructura del intercambio, el tipo de desarrollo cerrado en América Latina, la resistencia a las reformas y responsabilidad de realizarlas, el sistema de nuevas aptitudes y la concentración del poder económico y sus efectos políticos. "

Mar 1, 1964

By E. R. Bauer

Previous studies and research efforts have shown that noise-induced hearing loss (NIHL) is a problem in the U.S. mining industry. This is especially true in surface and underground coal and stone mining where large, noisy equipment predominate. Workers in coal preparation and stone processing plants have also been found to be subject to high sound levels that could potentially cause NIHL over prolonged periods of exposure. National Institute for Occupational Safety and Health (NIOSH) researchers have been conducting a cross-sectional survey of equipment noise and worker noise exposures in the mining industry to estimate the potential for NIHL within the mining community. One commodity recently surveyed was the extraction of sand and gravel from surface pits and by river dredging. Little is known about the noise environment and worker exposures in these environments, where processing and mining equipment similar to coal and stone are employed. To address the potential for NIHL in the sand and gravel industry, sound levels on and around the dredges and processing equipment were recorded to identify areas of high noise levels. Full-shift worker dosimetry, in conjunction with task observations, was documented to determine the relationship between exposure and source. This paper presents research examining noise on dredges, in several surface mine sand and gravel operations and in the processing facilities. The locations where workers are likely to be overexposed and were found to be most susceptible to noise overexposures are reported. Results indicate that there are areas on the dredges (crane, suction pumps, and diesel engines) where sound levels greater than 90 dB(A) are present. In addition, crushers and screens used in the processing of the sand and gravel also generate sound levels greater than 90 dB(A). Although no surveyed worker exceeded the Mine Safety and Health Administration (MSHA) Permissible Exposure Level (PEL) of 90 dB(A) TWA8, laborers, mechanics, oilers, helpers, pickers, and greasers are the workers likely to be exposed to hazardous sound levels and thus develop NIHL over time. Knowledge of the equipment noise, area sound levels, and worker dose levels is information that management and employees can use to reduce exposures. Exposures can be reduced in certain areas through administrative controls and through engineering controls applied to the noisiest equipment.

Jan 1, 2008

By Michael A. Piepenburg

The East Side Access (ESA) Project will extend Long Island Rail Road (LIRR) into midtown Manhattan via 11 km of tunnels, a new terminal station and associated support facilities. In addition to the hard-rock tunneling currently underway in Manhattan, soft-ground tunnels in Queens will traverse beneath Amtrak?s Sunnyside Yard and Harold Interlocking, the busiest rail interlocking in North America. This paper details ESA?s coordinated approach to interfacing with both Amtrak and LIRR with regard to the planned tunnels, shafts and related construction beneath or adjacent to the operating railroads. This interface includes integration of railroad staff, extensive presentations, reviews and agreements with the railroads regarding settlement mitigation, real-time automated geo-instrumentation monitoring, ground improvement, and geotechnical/environmental controls.

By Cristhian Vía

El artículo detalla una experiencia de implementación de microequipos trackless para el minado de vetas angostas, orientada a mantener anchos de minado económicamente factibles, rentables y seguros y a reducir significativamente la sobredilución. Se explica el diseño geomecánico para dimensionar aberturas y paneles, y se describe la estrategia de minado en cada operación unitaria tanto como los parámetros de control. Como resultado, se reportaron mejoras en todo el proceso de minado y se redujeron a cero de los accidentes por caída de rocas. Se perfeccionaron los indicadores de seguridad de la unidad, se redujo la sobredilución de 30 a 10%, y el costo de minado disminuyó de 34.17 $/Ton a 20.63 $/Ton.

Dec 31, 2020

By N. Nikolaev

La cantidad de métodos experimentales y analíticos no consideran los factores que influyen sobre el proceso de acción recíproca entre los elementos de sostenimiento y el macizo rocoso. En ese sentido, estamos en condiciones de separar dichos factores en grupos, reuniendo en uno los independientes, y en otros los relacionados entre sí. Por ello, el presente texto señala los métodos adecuados para determinar la influencia de un factor determinado o de un grupo de factores sobre el desarrollo del proceso a través de la determinación del tipo de cabeza de anclaje y de la pérdida de tensión final del anclaje con el transcurso del tiempo.

Jan 1, 1973

By Fernando Rodríguez, Jorge Chávez

En este artículo se revisan los principales aspectos relacionados con la gestión del agua en operaciones y proyectos mineros, se presentan importantes estándares y buenas prácticas internacionales (auspiciadas por el Consejo Internacional de Minería y Metales - ICMM), y se comparten éxitos y lecciones aprendidas de aquellas empresas que ven a este recurso como un activo en sí y un valor que puede generar múltiples oportunidades de beneficio colectivo.

Oct 30, 2020

By Juliana Parreira

La aplicación de sistemas automatizados constituye una oportunidad para incrementar la eficiencia de las operaciones mineras y alcanzar las expectativas de sostenibilidad en la pequeña y gran minería. En este sentido, el presente texto señala la implementación de la estrategia de la automatización en la calidad del ambiente laboral a través de la reducción de las exposiciones a ambientes inseguros que afecten la integridad de los empleados. Asimismo, los camiones autónomos de transporte de mineral (Autonomous Haulage Truck) aseguran condiciones de manejo constantes, optimizando el consumo de combustible y disminuyendo la emisión de gases del efecto invernadero; de forma que los costos de mantenimiento de equipos también son reducidos al tornarse predictivos y controlables.

Sep 14, 2009

For the sixth year in a row, the value of nonfuel mineral raw materials produced in the United States set a new record, reaching almost $17 billion in 1977. Data provided by the Bureau of Mines show that the 1977 value of domestic nonfuel mineral production exceeded the 1976 value, $16.7 billion, by 2 percent. The $17 billion worth of minerals was the basis for approximately $770 bill ion worth of processed materials of mineral origin. Output of metals decreased $360 mil lion in 1977, while that of nonmetals increased $670 million. Of the 22 metals produced, output of 12 increased, and the value of 13 increased. Among the 46 nonmetallic minerals produced, the quantity of 27 increased, and the value of 34 increased.

Jan 1, 1978

By Gregg Davidson, Lonnie Jacobs, Brett Zernich, Alan Howard, Robert Pintabona

All Rights Reserved. Printed in the United States of America. Information contained in this work has been obtained by SME, Inc. from sources believed to be reliable. However, neither SME nor its authors guarantee the accuracy or completeness of any information published herein, and neither SME nor its authors shall be responsible for any errors, omissions, or damages arising out of use of this information. This work is published with the understanding that SME and its authors are supplying information but are not attempting to render engineering or other professional services. If such services are required, the assistance of an appropriate professional should be sought. No part of this publication may be reproduced, stored in a retrieval system, or transmitted in any form or by any means, electronic, mechanical, photocopying, recording, or otherwise, without the prior written permission of the publisher. Any statement or views presented here are those of the authors and are not necessarily those of SME. The mention of trade names for commercial products does not imply the approval or endorsement of SME.

Dec 1, 2014